Unskilled and Unaware of It
Justin Kruger & David Dunning · 1999
"People with low competence in a domain tend to overestimate their own ability, because the same skills required to perform well in that domain are also the skills required to accurately judge good performance — so incompetence doubly disadvantages you: it produces poor results and simultaneously removes your ability to recognize that the results are poor."
Kruger and Dunning tested this across several domains, logical reasoning, grammar, humor, and found a consistent pattern: participants who scored in the bottom quartile on actual tests dramatically overestimated their own performance and ranking relative to peers, while top performers, if anything, slightly underestimated their relative standing, since they assumed tasks that felt easy to them were probably easy for others too.
The explanation is metacognitive, not just about ego: judging whether an answer to a logic problem is correct requires the same logical skill as solving the problem in the first place, so someone who lacks that skill lacks the tool needed to notice their own errors. This is why the effect is strongest in people with the least competence, not a general tendency toward overconfidence in everyone — the paper also found that as people's actual skill improves, often through training, their self-assessments become more accurate, converging with reality.
According to Kruger and Dunning, why do low performers in a domain tend to overestimate their own competence?
Read more about the topic
The explanation above is written with AI assistance. These are the originals — go to them to check it.
- Unskilled and Unaware of It (full paper)University of Michigan
The Psychology of Sunk Cost
"People irrationally continue investing time, money, or effort into a failing course of action specifically because of what they've already invested — even though that past investment is gone regardless of what they do next, and only future costs and benefits should matter to the decision."